SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '919d6da7f5b170a67a891989a36a6325676d19a89c7c332608278076bc6b0c07' 
  AND token = 'Lr5V+z0HomFju3AfTfIaE8NDdlTcrJQneU0NLA8AG5A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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