SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba016c266bd8645b0b2e3d7a8e60464277af94a1b2f35c4a474e92560f052fe6' 
  AND token = '203UKzNWkJWZrYsZXv/S8VAxqcJt/suqFVFzQCI+75Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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