SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d3442515b998f6992dba61ebb704cbfad02527794d809f2899a57ed991dd3f8' 
  AND token = 'nspM1S+1lHkhkDxcC7U5cuJN94f6JvZoCHZY4fgsxNU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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