SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ace5c93d4283a7abe94c10106c57d1293e09cb90c60fc5ac7e4d981698092f5b' 
  AND token = 'cme/Q9G1e8X0mwwsbl520DXiMKBliQPii8qWcCPo1SE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}