SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '951c2b325bbd3d166a42f81f6e3a5595ee17fdb0313be55f881142731864d158' 
  AND token = 'M807ffgU/XCF5PJP61yCE9kfTxxBG5WyS/sp4mX7vvk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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