SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05c99b3ea10697b66c95b500970ffef304fca964c0f9fdbd95c79ea04833ddb6' 
  AND token = 'cdId0WsdJDPMdRhVUociJ/PM9M8PIpq9m5xlIJRsS7A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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