SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c93188c74c5a62f29253d7140be7b01cc22255aaa3a69a03a3fd6ff917dc24c' 
  AND token = 'PMCGT6jBFDHczt2i/OXQqcwzoS5BCdG0iKGY5EJbqzI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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