SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '198bea1cc996f855ae5cb88bad85b764c1d365bbd07b9b454bab3c4778837f32' 
  AND token = 'r0rphv/Hv23ZgRpwGAKbnLHhS9RB91P0ZOjths2Y2zg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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