Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'e0286214e448b23138dd6213f5b5ad5753ef49efac19c3381fa059a206c5a2d3' 
  AND token = 'rJZu4loxgIFCzWyDReIDyinPUkDRa3/viWL3wJjxSi4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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