SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '933db573f309e29d2ca8d69d5115dc4313d5fd499aa2a99625b701e12d8aad8c' 
  AND token = '+PukZ3kw+ElUhQ7tl6/dDbZP2UENpMU3FgRqM+c8oSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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