SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5381e23117f2b2826f5968e92a484fd09d1a8aa97aa29dbd7daf28530112b6f0' 
  AND token = 'O6dj5f7z45xasdvtzCFUppWybBAJJp3HhBlSqvBif0o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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