SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'd3a9e8ab78287a5159805ab1efea97fff452380446b083a976d58fbc077ce464' 
  AND token = 'yGg+oivOunsWV0erou1CCsmkc/Ru2B3dQVdVKYh5dTQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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