SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b0d25b103952f072da89879eef7125ffbced49ce6a7274d66cb8594d64ccce9' 
  AND token = 'ne/8exzLKorB7W41pXd60t8fYTKrS3fIdYZba7GCwRw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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