SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd4d7af1d30705591342422779b706f52c64bb340d26fd93df352a92cee2debfb' 
  AND token = 'hp7s+5fqBTOpSKDQXTK3Bwu+vUrQ4yleZCPiMgDJZPc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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