SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '74817320d5cec38166dc12f0c0b0d34b0d1fb35ef961e42c981629c563583d00' 
  AND token = 'xJctyoa57R60kfCrigBQGlVAfHMNAv0gOarUPtwJJfo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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