SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64aaf5986faeb521b59745a3425de79a1056c8138377e207b4b67d38fa33648c' 
  AND token = 'u4HlOtRwzb70ki8hv+fvPTJU3Gq9ZPrFCC/EVGSRGsM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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