SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e415eeb2f4fde09175f8d5308fe1fc5410c254a746a9639094fcc581bcae6c3a' 
  AND token = 'IUr2zEC5lGtLn0SXRJhQMnu/BsQG0WvmhnxyrHI0oFg=' 
  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"
    }
  }
}