SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '00f5b4dc56b6b04e186cd76492e58f374658e3efef0b3c3d90c8af9a084bf0ef' 
  AND token = 'fNI3D1ztQP9l65jBzvKufXejnasFCo0LGo0fDmzyuvQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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