SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0218d35577dbe705bad38d06a005dae2cb506141d8309a7613d09f71192f9d45' 
  AND token = 'L1FbQKqQxYPZpo7BJhs0q+M7+GhX+NgpiBlppkhtjgI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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