SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c853ff674f5bcd1684ed764d6b3fd72f88c3668844d3413a5a2f96c673856375' 
  AND token = '5yyzDQ7SLTZU1uI/VkUOxyuapvtWsIiZ5hS1MIyPQCo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}