SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '5c2c6de58ded2cb3af3b3e246e3ea356aeba19f29ecc74d6984e03eea27a88d0' 
  AND token = 'VlzVCjY/owPqx9l9DSjGXm6mbvdlgRjL4/ISeKQ09KE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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