SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'beb4d97cadb90a95a14bf79c5ad2f1fab8ef55f0e3349f44472fefbf7e18b831' 
  AND token = 'hw18mLMeZclnsVyMD17qgvODbfBS1nWP2bDaBZfj7DE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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