SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89de2dd03cd74a877d41f567552cb6ea73b979333ed556e5cb743d7ed7ad440e' 
  AND token = '85lRR6kdv8L+nLDY+m+Ke14z5/W4SZVUlnNaYwqkhDw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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