SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '519c52f2b151c847ac8d068a3f648999190e3e3ae580b3aab9977f6ffe5f7ddf' 
  AND token = 'yKsdjvLlJC3x1u3RihBFVSLX55/KEwhvnwatmQKFKV4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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