SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'edb8d5d96a5ad292f8083790fb21b3455b9c7c2173dba04e08be88b49bab04b1' 
  AND token = 'UEK5wvZNfDUXaDezFFfLideRBMUPGaxBzsPBCnXwZwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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