SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ec98ff1bffb932a3be177989488d7e2941a3ce80db27d65d745718f3028d1803' 
  AND token = 'suRnjtofc2PmUNPFO6sG9UH9ka/MZonk+Q3S6G1rlvw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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