SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc2a1ea402277855b3cf2b18d0795c3667b979af114c9e6a00d0f3d54d233c73' 
  AND token = 'GO5rlmBVxLVFH2jqcPjvs4qWZQSOuAEpKU4fYSVu0QI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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