SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b917afd6527448487d6ef563e53758f144a1a5f938d499c55436fe184e932b7b' 
  AND token = 'yCq21LOHxeQCljBxnaypsyKvcXd4wqdRHx0QpUZvtYo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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