SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0455a63cc01630a28936862271c5eeb9b5fd70d28eafd890c5a22717292be2b0' 
  AND token = 'Q2n6YsnNZiMkqPje9f383P8I/OoENqjpZCaegQ6bn1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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