SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69eddfadf0f993824dd29995033ce1388a2a377ca626e293c0cb72baf5056d2d' 
  AND token = 'CqsL1eEZ1EMCnPlSEL0Z5Ng/+TnGzucD4ECjO8m7zkI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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