SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '010782309af9141071e396330db6070235d1f2e89dc1364065ccafd2f5c94c62' 
  AND token = '46jHXlKxS3b5y8UB9DlYd4nGkuPzxsvpXcHiY5cfaNA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}