SELECT 
  1 
FROM 
  q_lock_keys 
WHERE 
  key_id = '18b94720534c3c6964fa6564abab879d7f9632e01c4576b561078c222b42d33d' 
  AND token = 'SqbFGXmZ9Q6Qk8AfWFOWYR1MrmlfJZsmPUkaEPPjDJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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