SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f162a8ac858c674fb0b121d03378fbda1e516896e6a88b2da4485bcefe0f518b' 
  AND token = 'DPHKaiguQZOSyQIX4YtxmUlcVto+PJJz5umOUVilvF0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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