SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f80bdd827e5c8b7b5cc7f8554217b429e99393294fd2919a2fd32952073a0e8e' 
  AND token = 'P7KMQs3CPObH0UA1C45xzSKs5tiTXXgIBF+7Oahl3h0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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