SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c8d385edc7bdb3c636f280a0e5e0bed87ba3bd5aa2d3c597105c4669181ab5f3' 
  AND token = 'M+F7y5O7HCM6oGeW3rcgeC+3Ki2gB01sV7rRybWli5w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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