SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3f1515ae93559cff689b8bfdebfac6ea3ea457df47655530c8a0a91ae2d6e547' 
  AND token = '21Uk4jWtwAwuUrT3rCuxLBHqhLxij91hbBMnQ2UVoSU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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