SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5b7e95a998597f4e27e71fcdb35fa76a9d81d7d1197600b2e88a8787db98ebe3' 
  AND token = '6fvY6OBzl0AZqPUo+Uvugw/H8HMDq7h8sSoLwqntZH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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