SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c18b3e7ffc3057a2b2c3b844f63e2f042eb52a3a50a45372f3d9f97278cc48ef' 
  AND token = 'V6W4elw8J+oxm4YVbghxu7y+n6J8I3AmdYX10fG263E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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