SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e7e760fbb4d81c2dd1fffe371d9e1be88635c06b2da25decd81f1f756d66fbec' 
  AND token = 'aKLft99z3Vghqm973OSBpKMCZ5bccw65eDXS8XkpCaQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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