SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fd0e5eb9b7c6ee225621a128d6236409e8877d08e773b665d3cb952d2ff838e6' 
  AND token = 'iMrHswAcYnHNq71E3ehGXyOTQ2U+ct5N63vKp5GTB2s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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