SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '18e4688d14302c51c270db65ffe58071922131db499a9e458d39e0200a665cfd' 
  AND token = 'AIP6BIANsVD4eJwpcqgZRhArUn6teW3JpXfsjKnEuik=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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