SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '40c618411a66b58042e254edc20138f9f1e01632685629650d7a9fc36f2e3ede' 
  AND token = 'Yza3JOtUyLVap1WShKwkZFAFkgPv9c91wMbTJ9wrIqg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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