SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5e1cd45f8fdbe70a780337b1bf6a7d6f528ad14a34ea38b06b25da68326a7c64' 
  AND token = 'OnhdrfcoZcigF1tedvtBoZeCfb0yglU/BL0Wyc6nGfY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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