SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1b93707486ffa2f697c79fe61dc8989b7f9882aa9f33a0acf3d21b6b28b06d11' 
  AND token = 'BaEEK9PZ3J6VWer+Um0vk3Vz603jchFjm3yqLhthrpU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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