SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7e83534f19dd3725e44eaf41495f0ea81e86032d77ae887bb642257956c8ac1' 
  AND token = 'SbWob3H9/W6fkbb+o9XzOMCZL8LrYjR3AANLAnvYjr4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}