SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b77e2d301be789147ebe2a72ce5fb2ae473e1d2e4eb88525e79b52a7b2e31a2e' 
  AND token = '9so+XrUvUwGc7VA3GlWPurtcVBPD/EfQZ+cs95viWbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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