SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17fc0cee1e1b2057a5175045517c03d20a9d0b6510a0b6b088ddd607946daee0' 
  AND token = 'J/uRWgvwmMPKr+41QpLJskngqoKe4ZZfV/XuUpf+e54=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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