SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd24893d4894f264bbf220bb409853ece3cf87b81695badc73ce023a4362c9020' 
  AND token = 'GJjIsrl5MgceEB+b+cGG+0eGt/BPQwbysF5WQfgsIJo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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