SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e37208ad9ab776797d17212fd28c794e47e0c457146abbee3395ae85d0f5a810' 
  AND token = 'cyVCwFzuxMJHz/g7mQd/lxMXaTKnH8nrlCLPu2++bmY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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