SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a73d07287fabb538a7f344757032ca61a2cbbfaf83fc92b2e56ce83b8e2c38ea' 
  AND token = 'gIlsqq0jszOY+vLBQuUZPPz2Z0kFPdRJWuHWAT8O+i4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00068

JSON explain

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