SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8e6f2e2f8a8a37806ea2cd0bf24a19ac3f841c3fa3d941fdd0a53077ab114f73' 
  AND token = 's4FAt7cnBG3ci7JAJyorXYDFgt84df6NIasCB0xpUzY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}