SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e148c29ef1ce0fd91785cbfc576449915f97933d91afdb7ba7c3b337a0b5f0cd' 
  AND token = 'WUAkzTxYJxtACAuyH51avHPGhJnhePIZcgVJCFYn4fY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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