SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '958b459dae8947a1dde64a99bfd45b6849be21d990596da8894a91ddec725ae9' 
  AND token = 'LuUSHe4uGTtJwVLsqqvCX98ps5qDSl1OJHoNDznX7Ko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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