SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2638eba3f66e32afaa688a36456c05931cd1d0c22527ff92c95465797df519c' 
  AND token = 'iNHAZYvpThCzXxczcSK4kfNGFgHR4i0tH8mPqBLCAnQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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