SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccb95adbccc2694de248304e09f8fa13b184a181c98578a2e75e809bf62dc9b5' 
  AND token = 'JzfdBHijVg8Tbw2hn3Ik3K/rvbNBUadqunTY3lxejCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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